The present invention relates to electronic tokens and lock cores that cooperate to determine if access should be granted to the user of the token. More particularly, the present invention relates to electronic lock cores that are interchangeable.
Conventional locksets include a lock cylinder, a lock core that fits within the lock cylinder, and a token that cooperates with the lock core. The lock cylinder can take many forms. For example, the lock cylinder may be a padlock or part of a mortise lockset or cylindrical lockset. No matter what form the lock cylinder takes, the lock cylinder includes an opening that receives the lock core. Traditionally, the lock cores have included mechanical features that cooperated with a mechanical token to determine if the user of the token is granted or denied access through the lockset. See, for example, U.S. Pat. Nos. 4,424,693, 4,444,034, and 4,386,510.
Electronic access control systems interrogate a token having stored codes therein and compare the token codes with valid access codes before providing access to an area. See, for example, U.S. Pat. No. 5,351,042. If the token being interrogated has a valid access code, the electronic access control system interacts with portions of a lockset to permit the user of the token to gain access to the area protected by the lockset.
Access control systems may include mechanical and electrical access components to require that a token include both a valid xe2x80x9cmechanical codexe2x80x9d, for example, an appropriately configured bitted blade to properly position mechanical tumblers, and the valid electronic access code before the user of the token is granted access. See, for example, U.S. Pat. Nos. 5,826,450, 5,768,925, and 5,685,182. Many of these electromechanical access control systems use power sources and access code validation systems which are not situated in the lock core and token and are thus connected by separate circuitry to the lock core.
An interchangeable lock core that is configured to communicate with a token having an access code and a bitted blade in accordance with the present invention includes a core body, a lock actuator that is coupled to the core body for movement relative to the core body, a token communicator coupled to the core body, and a blocker movable between a first position wherein the lock actuator is fixed to the core body and a second position wherein the lock actuator is movable relative to the core body and means for moving the blocker between the first and second positions, the moving means being coupled to the token communicator and positioned in the core body. The moving means may include an electromagnet, a blocking member that is permitted movement by the electromagnet between the first and second positions, and means for storing energy acquired from the token interacting with the lock core and later using that energy to maintain the blocking member in the second position until the token is removed from the lock core. In alternative embodiments the storing means may be a spring or a permanent magnet.
An alternative embodiment of lock core includes a core body, a lock actuator coupled to the core body for movement relative to the core body, a token communicator coupled to the core body, and an electrical portion coupled to the core body. The electrical portion including a blocker movable between a first position wherein the blocker fixes the position of the lock actuator relative to the core body and a second position wherein the blocker permits movement of the lock actuator relative to the core body, the blocker being pivotable relative to the core body about the center of mass of the blocker. A power supply in one of the token and the core body provides power to the token communicator and an electromagnet controled by the token communicator, wherein the power supply provides current to the electromagnet under the control of the token communicator so as to provide a short pulse of current to the electromagnet. The blocker is sustained in the second position by a biasing mechanism separate from the electromagnet.
Alternative embodiments of the lock core include a passageway formed in the lock actuator, a tumbler barrel partially formed in the core body and partially formed in the lock actuator, the tumbler barrel being in communication with the passageway, and a plurality of tumbler pins contained in the tumbler barrel, the bitted blade engages a tumbler pin when inserted in the passage way and positions the plurality of tumbler pins in the tumbler barrel to allow movement of the lock actuator with respect to the core body.
Additional alternative embodiments of lock core include a first spring capable of biasing the blocking member toward the first position and a second spring capable of biasing the blocking member toward the second position, when the blade of the token is received in the passageway the second spring stores internal energy generated by insertion of the blade to bias the blocking member toward the second position regardless of the access code contained in the token. When the blade is received in the passageway, the electromagnet is energized if the token contains an authorized access code and the latch is decoupled from the blocking body which is urged to the second position by the energy stored in the second spring. The movement of the blocking body to the second position stores internal energy in the first spring. A third spring biases the latch toward engagement with the blocking member.
A method of a token interacting with a lock core includes the steps of providing a token having a token access code and a lock core, the lock core including a token communicator, a core body, a lock actuator coupled to the core body for movement relative to the core body, a blocker movable between a first position preventing movement of the lock actuator relative to the core body and a second position permitting movement of the lock actuator relative to the core body, an electromagnet, an arm coupled to the electromagnet for movement by the electromagnet between a first position in contact with the blocker and a second position spaced apart from the first position, a first biasing member configured to bias the blocker toward its second position, a second biasing member configured to bias the blocker toward its second position, and a token contact coupled to at least one of the springs, placing the token in a position to contact the token contact of the lock core and provide energy to the first biasing member, placing the token in a position to communicate with the token communicator of the lock core so that the token communicator can determine if the token access code of the token is valid, energizing the electromagnet if the token is valid to move the arm from its first position to its second position and permit the first biasing member to move the blocker from its first position to its second position, deenergizing the electromagnet to move the arm to its first position, and moving the token away from the token contact of the lock core to permit the second biasing member to move the blocker to its second position.
Additional features and advantages of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.